[glibmm] MemoryInputStream: SlotWithData: Make non-copyable

[Murray Cumming <murrayc src gnome org>]

commit 125eb4b37d7bf1e5d051621133be7a95f31978a1
Author: Murray Cumming <murrayc murrayc com>
Date:   Mon Dec 12 10:52:43 2016 +0100

    MemoryInputStream: SlotWithData: Make non-copyable
    
    Noticed by cppcheck.

 gio/src/memoryinputstream.ccg |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/gio/src/memoryinputstream.ccg b/gio/src/memoryinputstream.ccg
index 9c5068c..38126a4 100644
--- a/gio/src/memoryinputstream.ccg
+++ b/gio/src/memoryinputstream.ccg
@@ -30,6 +30,9 @@ public:
   {
   }
 
+  SlotWithData(const SlotWithData& src) = delete;
+  SlotWithData& operator=(const SlotWithData& src) = delete;
+
   ~SlotWithData() { delete m_slot; }
 
   void operator()() { (*m_slot)(m_data); }